A Study of Pore Closure in Large Bar Rolling Process Based on Relative Density

Porosity in the core region of the bar is a fatal defect in the bar rolling process. It significantly affects the product quality. In this paper, the concept of relative density is introduced to represent the porosity defects. The change of the relative density has been simulated using compressible rigid-plastic finite element method. By the simulation results, the influence of processing parameters on the pore closure in the core of bar is analyzed. The simulation results have been successfully used to guide the bar rolling process and improved the product quality noticeably.